Ok, here it goes again (taken from my previous post):
" I assume u know how to do the black frame test by leaving the lens cap on.
First, set ur ISO to 100, not AUTO. If not ur DC will set automatically to ISO 400 under complete darkness. At ISO 200/400 there'll be lotsa 'noise' even at short exposure.
Second, make sure that ur DC is cool b4 attempting to do the test. A warm DC and CCD will produce more noise' than usual.
Third, do the test in TIFF or SHQ image quality only.
Fourth, do a complete test from 16sec, 13sec, 10 sec, right down to 1/10 sec (or lower, up to you). The aperture, zoom and other settings should remain the same at all times.
If a bright pixel appears at all shutter speed...then this is a dead pixel. The only way to cure is to do an exchange (at AP or Olympus SG) or get Olympus SG to replace the CCD.
If the pixel doesn't appear initially but get more obvious and bright as the shutter gets slower, then this is a hot pixel. Don't worry, this is normal, even my DC has a few at slower shutter speed. What u can do is to pay Oly SG a visit and ask them to upgrade ur firmware...that'll will reduce (not eliminate) the amount of noise and hot pixels.
Actually anything that's noiseless and w/o hot pixels at 4 sec is very good already....anything beyond that is a bonus liao, I've already accepted this fact.
Hope these tips helps."